“Wholly and in every way, to gain any conviction about the soul is one of the most difficult things.” These words, appearing early in Aristotle’s De Anima (402a10-11), could well serve as an epigraph to the account of the soul we find in Sara Brill’s book, Plato on the Limits of Human Life.

Brill not only articulates something of the truth of this most difficult of things, she also identifies the source of the difficulty: the soul is “a uniquely plastic entity: plastic because it is subject to a wide variety of transformations with respect to its condition . . . unique because of its exemplary capacity to sustain itself as an entity through radical forms of fragmentation” (3). The plasticity of the soul is at the root of its elusiveness and of its allure.

Plato on the Limits of Human Life is divided into three parts, each dedicated to a different dialogue in which the plasticity of the soul emerges as a problem that prompts a political response.

Part I treats the Phaedo, where we learn to read Socrates not so much as arguing for the soul’s immortality as advocating a philosophical way of life committed to caring for a dynamic and malleable soul. This way of life, Brill argues, takes a stance toward psychic plasticity—neither reifying it nor obscuring it—that requires a particular form of human community. This becomes clear not only as the drama of the dialogue unfolds and each argument for the immortality of the soul fails, but also, and more poignantly, in the myth of the true earth at the end of the dialogue which, Brill argues, “provides Socrates and his interlocutors the resources for considering the effects of their actions on the community in which they reside in this life” (79).

Part II turns to the Republic, where we encounter the soul of the tyrant, and learn both the excessive character of the soul and the important role the city can play in limiting it by laws designed to empower it to live a fulfilling life. Here, what Brill calls the “prosthetic function” of the city and its laws (150) begins to come into focus as the central principle around which the book is organized: psychic plasticity requires a prosthetic limit if human life is to flourish. The city serves this prosthetic function. Given the nature of the soul, human flourishing is won or lost only within the confines of a city: psychology is politics in Plato.

In Part III, then, we are offered a reading of the Laws, or more precisely, of the preludes the Athenian Stranger appends to the laws of Magnesia, which themselves demonstrate the therapeutic function of law itself. Here we learn not simply that laws have a prosthetic character (169) but more broadly, on a cosmic level, it is mind in its capacity to limit the excessive acts of the soul that ensures the good order of things (198). What unfolds on the human level with regard to finite souls and the city plays itself out cosmically as the motion for which the soul is responsible is limited by mind, a limit that “is somehow both ‘external’ to [soul] and intimately related to it, intimately its own” (198). Soul, then, is shown to “tend toward prosthetic limits”, be it the laws of the city or the limiting capacities of mind. Thus, Brill situates the soul in its relation to the city into a wider cosmic order, suggesting the manner in which, for Plato, the city, itself an expression of mind, emerges as a necessary and enabling limit to the plasticity of the soul: “Mind and its closely related phenomenon, law, are precisely such enhancing and augmenting limits” (198).

In a sense then, although she does not refer to it, Brill’s book can be read as an eloquent explanation of Aristotle’s claim in the Politics that “a human-being is, by nature, a political animal” (1253a2-3). Indeed, the most compelling aspect of the book is the way Brill offers the reader insight into an ancient worldview in which human flourishing depends less on the individual’s ability to cultivate a character capable of crafting a fulfilling life than on the city’s capacity to fulfill its prosthetic function in limiting the plasticity of the soul. The idiom of prosthesis, Brill argues, is “uniquely suited to describe the relationship between the city and the soul in Plato,” because “of its semantic association with replacement, augmentation, and generation, with filling in, enhancing, and innovating, and because it is reducible neither to the natural nor to the artificial, yet is answerable to the living” (5). As psychic prosthesis, the city enables, or fails to enable, human flourishing.

As the above outline suggests, this book is what Socrates suggested to Phaedrus every speech ought to be: “organized like a living being with its own body, lacking neither head nor feet, but having both a middle and extremities, written so as to complement both each other and the whole” (Phaedrus 264c2-5, tr. Cobb). The chapters on the Phaedo are the feet of the text, providing us not only with an account of Plato’s “psychic geography”, but also offering us a picture of an individual soul confronting the ultimate limit. The Republic, situated in the middle of the text, not only connects the feet to the head, but contains the heart of the argument for the interdependence between the soul and the city (150). Indeed, at the very midpoint of the book we learn that the soul and the city are co-constitutive (105). Finally, the book comes to a head in the discussion of mind and law in the Laws. There, Brill summarizes a main thesis of the book when she writes: “the role of the city is to provide prosthetic limits to the human soul by means of its laws, customs, institutions, etc. In doing so, it translates or applies orderly cosmic motion to human affairs and thus assures the flourishing of the whole” (204).

The organic coherence of the book, though shown, is not explicitly articulated. This lacuna leaves the reader wondering at first precisely why these three dialogues and not others are uniquely positioned to treat “psychic plasticity as the central problem with which Plato grapples” (3). Other dialogues, of course, are conspicuous in their absence. The Gorgias, for example, is poignantly missing when Brill traces the limitations of the analogy between disease and vice at work throughout the Republic (112, 140). Her account of how the death penalty imposed upon a vicious criminal elucidates the difference between disease and vice (because it illustrates the mediating role of the law that is absent in the natural process of healing) is a highlight of the book (148). But that account would have been enriched by a reading of the Gorgias, another dialogue in which the analogy between disease and vice is made explicit. The absence of the Phaedrus—with its famous image of the soul as a charioteer and two horses—is felt as well when Brill emphasizes the manner in which eros and thumos animate the soul, and further still when she develops the prosthetic function of the mind at the end. If then, this book lacks neither head nor feet, still, much remains to be fleshed out regarding the political dimensions of Plato’s psychology from other dialogues.

Ultimately, however, the success of this book lies in the manner in which it combines a close and nuanced reading of the Platonic texts with an ability to trace a wider story about the nature of the soul in Plato. It resonates with and is exemplary of a great deal of innovative and insightful recent scholarship on Plato emerging from scholars associated with the Ancient Philosophy Society. If the soul requires the prosthetic function of the city to flourish, perhaps excellent scholarship needs the prosthetic function of a community of scholars as committed to rigor as much as to one another’s work. Brill’s book should thus be placed alongside and brought into dialogue with the recent books on Plato by scholars associated with the APS such as Jill Gordon, Marina McCoy, Sean Kirkland, S. Montgomery Ewegen, and Anne- Marie Schultz.1 And it should be read as belonging to a tradition of scholarship that extends from thinkers like Drew Hyland and John Sallis.2

From Sallis, Brill learned the importance of attending to the performative elements of the dialogues. She follows him (and Eva Brann)3 in emphasizing how the action of the Republic itself creates a community among the speakers of the dialogue (89). The community that emerges from the action of the dialogue is an explicit focus of Brill’s reading of the Republic, but strangely enough, it does not inform her reading of either the Phaedo or the Laws, although those two dialogues enact communities as well. This disjunction is more pronounced in regard to the Phaedo insofar as an account of the community of friends that emerges from that dialogue would have provided further support for Brill’s argument for the prosthetic function of human community. For their shared experience of Socrates’ death, and his prosthetic insistence that his friends not become misologues but instead continue to allow their lives to be animated by words oriented toward truth, is precisely what enables them to go on, and perhaps even, as Phaedo seems to have done, to flourish as the founder of a school. 4 With regard to her reading of the Laws, more attention to the action of the dialogue might have added texture to Brill’s account of the preludes.

Even so, this book stands as an important contribution to the scholarship on Plato’s psychology by artfully articulating the interconnection between the soul and the city. It has the further virtue of offering a compelling example of how detailed readings of Platonic myths, readings that recognize the myths as critical appropriations of traditional ideas and thus as at root dialogical (6), can have deep philosophical significance.

However difficult it is to gain conviction about the soul, we have been given some purchase on it by Sara Brill’s excellent book.